Study on population genetic diversity and variation of Calamus poilanei Conrard in the Southern Central Highlands, Vietnam

Pham Trong Nhan ^a, Le Hong En ^a, Nguyen Van Ket ^b, Le Ngoc Trieu ^b,*

^a Forest Science Institute of Central Highlands and South of Central Viet Nam, Lam Dong province, Viet Nam
^b Faculty of Biology, University of DaLat, Lam Dong province, Viet Nam

Abstract

The genetic diversity and variation of two Calamus poilanei populations in the Southern Central Highlands, Vietnam, were comparatively assessed using three different DNA fingerprinting techniques: Start Codon Targeted Polymorphism (SCoT), Inter Simple Sequence Repeat (ISSR), and CAAT Box-Derived Polymorphism (CBDP).

Combined data revealed that the genetic diversity of the Cat Tien population was characterized by expected heterozygosity (H_e) = 0.2498, Shannon index (I) = 0.3772, and the proportion of polymorphic bands (PPB) = 78.47 %. The Dak R’Lap population showed slightly higher values: H_e = 0.2529, I = 0.3826, and PPB = 82.3 %. At the metapopulation level, H_e = 0.2611, I = 0.3998, and PPB = 92.34 %. Pairwise genetic similarity coefficients between individuals (SCs) ranged from 0.536 to 0.933 (average = 0.755) in the Cat Tien population, from 0.565 to 0.914 (average = 0.770) in the Dak R’Lap population, and from 0.512 to 0.933 (average = 0.755) for the metapopulation. Gene flow between populations (N_m) was high (12.88), leading to low genetic differentiation (G_ST = 0.0374) and genetic distance (D = 0.0264). The majority of total genetic variation occurred within populations (94 %), with only 6 % among populations.

Although the three techniques showed no consistent correlation in estimating H_e, I, or PPB, they showed agreement in estimating N_m, G_ST, and D. Among them, SCoT was the most effective in this study, considering its overall utility.

These findings contribute to conservation planning for Calamus poilanei and provide orientation for future studies on related species.

Keywords: SCoT, ISSR, CBDP, Population genetics, Rattan

Sources: Ecological Genetics and Genomics, 37 (2025) 100419

Link: https://doi.org/10.1016/j.egg.2025.100419
 

Fig. 1. Location of surveyed Calamus poilanei populations and geographical barriers between them

Fig. 2. Unweighted pair group method with arithmetic mean (UPGMA) dendrograms for genetic relationships among individuals within Cat Tien population based on combined data.
Note: In Figs. 2–4, the Roman numerals on the right indicate the cluster numbers. Vertical dashed line indicates the similarity threshold used to delineate clusters.

Fig. 3. Unweighted pair group method with arithmetic mean (UPGMA) dendrograms for genetic relationships among individuals within Dak R’Lap population based on combined data.
 

Fig. 4. Unweighted pair group method with arithmetic mean (UPGMA) dendrograms for genetic relationships among individuals belonging to species in surveyed region based on combined data.
Note: blue circle: individual from Cat Tien population, red circle: individual from Dak R’Lap population.